tv [untitled] August 22, 2012 10:00am-10:30am PDT
>> good afternoon. we are very forge to have with -- "fortune" to vo with us some guests who are going to speaking to us about balconies and problems and what maintenance issues you should be paying to. we have dave from lynnagain, associates from what you normally would call a termite inspector. it's actually a structural pest control company. is that right?
>> that's right. >> we'll talk more about what license pest control folks do and why it's so important to know them and to know dave. and a structural engineer who looks at lots of decks and balconies and tries to figure out ways to fix and solve problems. and sometimes looks at the reasons that problems occur and called in to do the forensic investigation of that failure as well. and of course, harvey is here with pat. thanks for joining us, harvey. and i'm chief building inspect, lawrence cornfield. we have a bunch of slides we're going to go through today that i hope will give us sort of a basis to ask questions and focus our discussion. most of the decks that we see that we're going to talk about are made of wood. san francisco is a city built primarily of wood, in fact.
and for better or for worse, it used to be wood was cheap and readily available and now, wood is expensive and you know, sometimes it's not even appropriate green material anymore. in fact, steel is preferred for a lot of uses because it can be recycled and reused. especially really good redwood and stuff that used to be used for exterior decks is almost unavailable but it's extremely political lynn i correct to use this clear redwood. now there's other materials including metal and other kinds of fabricated lumber that's kind of glued up. and you lee a lot of it. >> it's different types of pressure treated. >> so what used to be used almost exclusively is redwood in our area. and you still see huge amounts of old redwood. >> and that was all first growth 300-year-old trees that they just cut it down and the wood was perfect.
that doesn't exist anymore. >> that's right. so one of the requirements for the use of wood in the outside is it really needs to be decay resistant or as they say in the building code, wood was a natural resistance to decay is the correct word. so here, i brought a few samples just to talk for a second. here. tell me what this is, you guys. >> that's crappy dug fir. two-by-four. >> if you use this outside, what happens? >> if you use that wood which is about a 20-year-old tree, you might get three years of life before it falls apart. >> ok. and the building code does not allow you to use wood that doesn't have a natural resistance to decay in decks outside. it requires that you use either treated wood or redwood or some other wood with a natural resistance. and there are others. by the way, it's not just
redwood. cypress, cedar. >> one of the largest structures in san francisco is made up with alaska cedar. >> let me ask you here. anybody know where this very large structure made of alaskan yellow czar, a beautiful -- cedar elegant structure. anybody know? you know? >> at&t park? >> at&t park. give this man a ticket to the ballgame. because down at the ballpark -- >> is a coke bottle made out of alaskan cedar. >> it's a giant coke bottle with alaskan cedar ribs and pat was involved in it and -- >> they fabricated it and sailed it down the bay, weighed about 150,000 pounds. it's a big coke bottle. >> and what do we have here?
what can you tell us about this stuff? >> treated material that we use for framing, for decks. people use this for decking. right here, it looks like it's treat on the ends. which i guess you're going to get to treating cut ends on material that's freshly treated. that's the new stuff though. >> yeah. >> and this is treated with copper sulfate which forms a reaction with any nails that you use unless you use stainless steel. >> we'll talk about that in just a second. because you have to use the right kind of fassners, nails, and other clamp and clips and joyce hangers to match the kind of woods you're using. and what is this stuff here? >> that's the old pressure treated which is copper arsenic. and you want to wash your hands now that you've touched it. because you've got arsenic on
your hands. >> used to be arsenic-based treatment. the federal government threatened to regulate the industry, pressure treated lumber industry. so the industry got together and voluntarily regulated itself, about seven or eight years ago and said we're going to phase out arsenic. we're going to sell all the existing stock and we're going to sell only this new safe copper-base treated material. it turns out the new copper-based treated material as unintended consequences. not so much for health causes but because it is highly corrosive to most fasteners. and i was saying this right upfront that you should be very careful that you have to use hot-dipped galvanized connectors or stainless steel. so here we have -- i'm going to pass around for you -- >> it's hot. >> -- an example of a hot-dipped
galvanized connector. this is a lag bolt and you can look closely and you can see it's got the roughness, coarseness, the trying where shape pieces of zinc dipped in zinc to make this a hot dipped connector. >> this one looks nice and shiny. this is elect roe plated galvanized. it doesn't give you a thick enough coating. >> so what happens it corrodes and if you expect it to stay together, you will find it to corrode. it corrodes very, very fast. do not use either common nails that are uncoated or connectors or elect roe galvanized connectors.
ok. let me pass this around. i won't pass the arsenic around. i'll just pass these around. >> and what happened was they were making playground structures out of the arsenic based pressure treated wood and kids were coming back home with these high levels of arsenic and someone figured out that they were going out and playing on play structures that had just had rain on them. the rain leaks the arsenic on. kids rub their hands on the wood and where does the kid put their hands? on their mouth and they were getting high arsenic level. so they just banned it. saying there's no safe way to use his stuff and keep it away from kids or dogs. >> so we will also look at one or two metal frames, decks and balconies. our first slide here today is sort of a typical residential deck. these are slides taken in san francisco. and this just has the various pieces of decks that we talked
about. it's got posts that go down to the ground. the posts are connected to a beam underneath the deck that holds it up with metal connectors. the beams -- the beam is at the end of a bunch of joist that are in this case, attached to the building. and then on top of that, it's a decking surface. and then guardrails, which are now called guards, they're no longer guardrail. the building code changed january 8, 2008. the spacing is very title. so this is sort of the -- tight this is an overview of what the deck is. here's one. the same one, i think. close up. you can see the metal connector. by the way, these metal connectors are very, very
inexpensive. and here's -- here's a typical simpson strong tie metal connector. this is a particularly useful connector underneath your house where a post comes off and it holds a gutterer or a beam. this costs $2.59 and it can save your house $20,000 of damage for this $2. so i encourage everyone to go through their building inside and out and find reasonable places to put metal connectors. they're stroorly strong. very inexpensive and those install with the proper kind of nails. >> they call them chicos. >> chicos. and they have these that are galvanized or for use for outside. and they're listed that way. ask at the hardware store. and the nails are also lusted for -- listed for outdoor use.
we see the bolts that hold the guardrails up. and it's bolted straight through the end of the beam. and those have to be also galvanized. they have washers on them at both sides. and we can see at the ends of the guards themselves, we see nails and all of those things have to be toxic galvanized. those would typically -- i'm a little concerned about nailing stuff on there. what do you think about nailing that stuff on? >> well, if you push on it, the nail would just pry right loose. if you're going to use something like that, you want to use light screws. those are small for lag screws. things stay tight. >> the building code actually says that you are not allowed to use fasteners structural systems with walls. so the resistance usually, you want to use these things in shears so they're not sliced it's easy to pull a nail out. in this case, where we have a required resistance, we are not really supposed to be using a
fastener in with withdraw. the thing that's preventing it from going, it's not pulling a nail up. so the way to solve a problem like this nightclub put another board across the outside of it and lag bolt or through bolt all the way through into the joist behind it. that would really hold that thick on. i love this. this is a little bit of an example of how incrementally decks change in san francisco. and i think we'll see some more pictures. a lot of things you started out as like an outdoor porch, maybe. and then the next thing you know, it's a porch with a washing machine. and pretty soon, it's closed in a little bit. and then the next thing you know, they put the refrigerator out there. and 20 years later, it's a carpeted room. this is san francisco. and all over, you see -- and then on the back of that, there'll be a little deck. and then they'll start over again. that will be fun.
there will be another little deck. if you look around san francisco, you can see all of these incremental developments and this is the step towards that end. >> you've got windows there. >> well, they put windows. this is a security issue. and i can understand that. but we see this happening all over the city. this also has the wind-driven rain which forces its way through the deck on to the big sliding doors that are inside here. wind-driven rain is a serious, serious problem for many buildings, especially new buildings in san francisco. wind-driven rain where there are sliding doors or patio doors or deck doors is the reason that there's typically a step up at a door when you have a deck. >> for existing construction. >> for existing construction. now for new residential construction, there are disability access laws that does not allow to you have a step up
up at that or down at that deck. one of the big issues especially the high-rise buildings is how do we make the deck fully accessible and deal with the wind-driven rain issue? probably not to have a wliding door but have a swinging door. because we have sweeps. very easy ways to deal with waterproofing. very hard to deal with sliding doors. we have all sort of ramp arrangements that help you get down the ramp area. something like this reduces the wind-driven rain effects on somebody's outdoor deck area. you would need to get a building permit if you were to enclose your deck like this. changing the nature of the deck. by the way, decks do need building permits. here's a deck this has got only a couple of unusual features. this has got a metal guardrail around it, or guard. this deck has a piece of plywood or something on the bottom that
conceals the joist. now, it conceals the joist which means a couple of things. what -- tell us. dave, tell us what you do if you went out and looked at this deck. what would you do as a structural pest control expert? >> we do a visual inspection. i also keep people with me so i can probe into the wood. one of the first things we would note is there's no ventilation on the underside of that deck. if any moisture gets in there, it's going to be trapped. it's going to increase the amount of dry rot. >> now the building code for years had a requirement if you had an outdoor requirement, you must put venlation. -- ventilation so that moisture does not >> one of the rules in all waterproofing design is everything leaks. every wall leaks. and you have to put in a weed to put the water out. if you do something like this,
you're going to trap the water because you let the water in are the top and you don't let the water out. so the cardinal rule, you always allow a weep to allow the water to escape. >> what do you mean by a weep? >> a hole or a track with preforracings to allow things to breathe. -- preforations to allow things to breathe. >> so what are the normal places that you would look for failure in this kind of a deck? >> for myself, typically the underside of the surface, the plywood on the bottom. where the post attach. anywhere there's an attachment with two pieces of wood and it's not concealed, water's going to get attached there. and the surface. i'm assuming this is some sort of a deck coding of walk-on
surface. we look at that to make sure it's not worn. >> here's your -- that's my -- if my dog will behave himself. here's the joist can lever. and they don't ever flash correctly the first time. these joist, they corrected the second time because it's real expensive to fix. >> ok. we're going to look at a can lever and a flashing detail. so when this joist sticks out of the building, how do you keep it waterproof at the point where it sticks out of the door? that's a major, major problem. and there's a lot of flex at that location. if there's any rot there, that's where the -- >> it's going to collapse. >> i love this house. we call it the darth vader house up on i think it's like 13th
avenue, up in the sunset heights. and when i went by there, you can see the decks. here's a previous slide years gone by with all these cantalever decks with interesting coast guards. guardrails that have glazing to keep people from falling out. they don't meet the garrard rail requirement which is a -- so here i was driving by a couple of years later. and all the decks had been cut off the building and they were sliding the debris down the chute that you can see. it is a common problem and very expensive to repair as well. this has a lot of the features that we're talking about, the
posts, the beam, the rim joist at the end of the joist they're holding the deck up. a solid guardrail in this case. nobody's going to get through that. and all the stuff that people always attach to their decks. >> [laughter] >> always. everything. that's a standard detail. showing one of these connectors, a heavy duty poster beam connector with through-bolts in it. >> this is a common mistake people do. they get the pressure-treated wood and then they paint it. you don't paint pressure-treated wood. because then all you're doing is you're creating a seal around the wood that will keep the water in. you can stain it, which is what the coke beaumont is. you can put a -- bottle is. you can but a semi-transparent stain but someone's crossing the line when they're painting the
pressure treated wood and that accelerates your dry rot. it takes longer for the treated material to deteriorate. >> another thing you can see in this slide is these boards, the deck boards themselves that you walk on are very, very close together. now typically, you water to be able to pass between those boards. they will fill up with debris and dirt and, you know, pine needles and so on. and what happens then as it traps water between the boards and that will lead to rot between the boards. so if you have, you should have space between the boards. you should have a way to clean them out. so a weekend chore is to either get a high pressure water spray thing to try and clean all the stuff out between the boards or to take something like a small saw blade -- >> or a spatula. >> or something sharp and clean the boards so they can drain. and once they're drained, then
air dry and reduces the -- >> but what you actually do, the dirt becomes a sponge. the sponge holds the water. and so long after the rain, you still have this wet pocket, dry rotting at the wood. you want to keep everything nice and clean. >> so your regular maintenance is to get out there and make sure it's clean between all the boards. >> particularly a lot of pet. i see a lot of pet hair. that's the one thing. when i inspect with open decks, i will take out a dull screwdriver and i will probe down the joist to see where there's damage. that's where most of the damage that we see start to develop. is right where that space is because of the lack of cleaning in that area out. >> so dave, this is a good time for to us ask you. structural pest control infection. when are you usually out looking at this stuff? >> typically, now we do presale inspections before real estate
agents will list them out. and do our inspection we used to do for the buyers. we look for the wood destroying organisms be it dry rot, terms. -- termites. beetles into decks, particularly decks we built years ago. may have untreated -- but we look for dry rots. we also do the repowers. -- repairs. repairs -- repairing decks on cantalever decks. >> and then you also get involved when there's litigation. >> some people say seems like there's a conflict. you're doing the inspection. you're providing the price to do the work and then you're doing the work. isn't there some kind of conflict here that you might be saying that stuff has to be fixed that may be more than would be absolutely necessary?
>> we're regulated by the structural pest control board. and they actually have rules and regulations and they tell the termite companies what we have to. notify on our reports what problems we have to identify. what type of correction we're supposed to make for that problem, and then of course if we are actually in the business of doing it, we're required to submit an estimate for the repairs if it's requested. and it's pretty cut or dry. either there are termites or there are not termites, you know? if you read our reports, it will always, you know, self-consume. you can get reports from different people. the findings should all be the same. either it's termites or not. whether there's dry rot or not. sometimes there may be differences of opinions as far as the methodology of the repairs. >> it's one of the industries that has one of the best reputations for san francisco in integrity. you hear issues about different industries but special pests
have would have been the best reputation. >> here the he building, we almost never find issues with special pest controls or work. we deal a lot and i have to agree with pat, it's an extremely high level industry. so thank you for what you do. >> [laughter] >> ok. ok. let's move along. ok. so here's -- >> there it is! >> here's point where we have an issue. >> [laughter] >> ok. where the deck attaches to the building is the number one problem for water intrusion. >> well, where it penetrates through the skin of the building. >> ok. so what do we see here and what's going on? >> work for him. >> [laughter] >> there's no flashing. hidden underneath the shingles. and what you're going to find it you've got that brown spot. looks like you got a nice little dry rot occurring -- on all the boards there. and if you were to remove the
planks on top, you probably would find a good chunk of dry rot missing at the top of the joist. and as you feed into the top of the joist, you reduce its capacity. and it's not proportional. if you have a 10-inch joist and you lose an inch, that's 20% of its capacity. you lose two inches t like 40% of its capacity. so dry rot can be very, very dangerous if you're not properly paying attention to it. >> and that's because these joists typically are cantalever. and you're relying on the top of that joist as you walk out on it, you're pulling the top of its tension and you imagine slicing on top the tension number. >> the lack of the flasher is not just for the deck either but it's also for the wall frame that we'll find damage in there as well. once you open that and put the flashing details in there, we'll find that the structural framing
are also compromised. >> so it's not a bad idea i guess to say if you have a house in san francisco to have somebody who's an expert come out and look at your deck and your flashing, to look at it even if it's not a structural pest control report done at the time of sale. it's a good idea to have somebody come out and just take a look at it and tell you what you might do before it becomes a big problem. and in fact, this might be a good time for me to introduce rosemary boss i can who is here. -- boski who is here. come on up here and give us a little talk about what's about what's required. the housing ordinance requires that all -- about eight years ago, that required all decks and exterior balconies, metal or
wood in multi-family buildings need to be certified, need to be inspected and certified to the city every five years? >> five years. >> every five years. this is rosemary boss i can, chief housing instructor and she has some handout about this new regulation. >> this particular affidavit and notification is on the department website. so if you go to -- >> sf.org. >> and click on the housing inspection services, this document is there for you to download. and what we're doing with this right now is the san francisco housing code requires the city and county of san francisco to do inspections of participate buildings and hotels at least once every five years. so while we're going thus thru this process, we're inserting this particular affidavit and notification in the appointment request letters going out to the
property owners so that we could have a field inspector actually explain this process. this is not meant to necessarily be always done at the same time. we're just introducing it this time to get the information out to the property owners so say that know that this particular requirement exists. why do we put this in the code? we put it in the code because we realize that the -- with the amount of buildings we have out there, their type of construction, the age of these buildings and the amount of inspectors we have, we can't really get at the issues with decks, failure, dry rot and all these issues just with the staff we have. so one of the things that we're wanting the proper owners to do, to regularly survey their buildings for this kind of problem, get a licensed industry professional like these good gentlemen here to my right, to look at these buildings in the level of detail that a